Study: Even lead-free ammo may harm lung function

Nov. 1, 2013 - 01:13PM
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A new study suggests that firing small arms causes a decline in lung function that lasts at least 24 hours after shooting and possibly has long-term respiratory effects.

Alarmed by reports that Norwegian troops were getting sick after firing lead-free “green” ammunition, scientists with the Norwegian Defense Research Establishment, Oslo University Hospital and the Norwegian military decided to test lung capacity in troops before and after they hit the firing range using both lead and lead-free ammo.

They found that all 55 subjects had trouble breathing immediately after shooting and diminished capacity 24 hours later regardless of the type of ammunition used.

“The subjects got respiratory symptoms and metal fume fever,” said the researchers, including lead author Anne-Katrine Borander of Oslo University Hospital, in an email to Military Times. “Fumes released during firing of small arms are highly complex mixtures of gases, vapors and solid particles.”

For the study, the Norwegian troops — 55 otherwise healthy, non-smoking service members — fired the HK416N with 16.5-inch barrel. The subjects were given a spirometry test before firing, about an hour after shooting and a day later.

“This is due to irritation of the airways. Respiratory irritation can be caused by irritants, general dust and metal particles,” researchers said.

The study has a number of limitations, according to the scientists, including that it was not designed to figure out what level of exposure causes symptoms to appear.

They said the research is part of an ongoing NDRE effort to study the particles emitted by gunsmoke and their effects on lung cells.

“One important question is whether repeated exposure to gun smoke can produce chronic respiratory or immunological diseases or impair lung function in the long term,” Borander and her colleagues said.

The researchers suggested military leaders could help reduce long-term risk by developing and using a lead-free ammunition that emits lower levels of metals such as copper and zinc, ensuring that shoot houses have efficient ventilation systems and encouraging troops to report if they feel sick.

The findings were presented in September at the European Respiratory Society Annual Congress and will be published in three scientific papers in the coming months, according to Borander.